1. Field of the Invention
The present invention relates to circuit interrupters generally and, more specifically, to those kinds of circuit interrupters having a housing with a base and cover, and an operating mechanism positioned within the housing.
2. Description of the Prior Art
Molded case circuit breakers and interrupters are well known in the art as exemplified by U.S. Pat. No. 4,503,408 issued Mar. 5, 1985, to Mrenna et al., and U.S. Pat. No. 5,910,760 issued Jun. 8, 1999 to Malingowski, et al, each of which is assigned to the assignee of the present application and incorporated herein by reference.
Circuit interrupters typically include a housing having a base and cover. Within the base is positioned an operating mechanism that is interconnected with the contacts of the circuit interrupter. In the prior art, the operating mechanism sometimes is held in place by an independent securement mechanism such as orbital riveting. However, such independent securement adds to the cost of assembly, and slows down the assembly process. For those reasons, prior art circuit interrupters have sometimes employed a xe2x80x9cfloatingxe2x80x9d operating mechanism that is not secured by an independent securement mechanism. Instead, other structures of the circuit interrupter are usually relied upon to secure the operating mechanism within the base upon completion of the assembly process. For example, the positioning of the cover onto the base can be used for that purpose, with the bottom of the base designed to contact a top surface of the operating mechanism to hold the mechanism in place. However, securement provided by this latter technique can suffer from variability in parts and slight aberrations in the molding process, potentially resulting in the operating mechanism being insufficiently engaged. This can lead to improper positioning and functioning of the operating mechanism.
It would be advantageous if a circuit breaker existed that enabled a floating operating mechanism to be implemented with sufficient engagement thereof notwithstanding variability in parts and slight aberrations in the molding process.
The present invention provides a circuit interrupter that meets all of the above-identified needs.
In accordance with the present invention, a circuit interrupter is provided which includes separable main contacts, an operating mechanism interconnected with the separable main contacts, and a housing in which the separable main contacts and the operating mechanism are disposed. The housing includes a cover that is positioned on top of a base, the cover including first contact surfaces for contacting and mating with second contact surfaces of the base. The cover also includes a contact region. The operating mechanism includes a support member that is situated within the base and which has an upper surface with a raised region. The raised region is positioned to make contact with and pierce into the contact region before the first contact surfaces of the cover fully mate with the second contact surfaces of the base.
This and other objects and advantages of the present invention will become apparent from a reading of the following description of the preferred embodiment taken in connection with the attached drawings.